Piperazine, 1-(cyclopropylcarbonyl)-, Monohydrochloride

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred mixture of 3-formylbenzoic acid (450 mg, 3 mmol) in anhydrous dichloromethane (20 mL) was added triethylamine (758 mg, 7.5 mmol), 1-hydroxybenzotriazole (466 mg, 3.45 mmol), followed by 1-ethyl-3-(3-dimethylamino propyl) carbodiimide hydrochloride (629 mg, 3.45 mmol). After the addition, the mixture was stirred at room temperature for 40 mins. Then the mixture was cooled to 0° C. and cyclopropyl(piperazin-1-yl)methanone hydrochloride (629 mg, 3.3 mmol) was added in portion-wise. After the addition, the mixture was allowed to stir at room temperature overnight. The mixture was diluted with dichloromethane (50 mL), washed with saturated citric acid (100 mL×2), followed by saturated sodium bicarbonate (100 mL×2), brine (50 mL), dried over anhydrous sodium sulfate, and concentrated to give 3-(4-(cyclopropanecarbonyl)piperazine-1-carbonyl)benzaldehyde (810 mg, yield 94%) as a light yellow oil. 1H-NMR (400 MHz, CDCl3) δ (ppm): 0.79-0.85 (m, 2H), 1.00-1.04 (m, 2H), 1.73-1.76 (m, 1H), 3.47-3.77 (m, 8H), 7.62-7.66 (t, J=7.6 Hz, 1H), 7.70-7.72 (d, J=7.6 Hz, 1H), 7.95-7.98 (m, 2H), 10.1 (s, 1H); LC-MS (ESI) m/z: 287 (M+1)+. After the addition Then the mixture was cooled to 0° C. After the addition to stir at room temperature overnight washed with saturated citric acid (100 mL×2) dried over anhydrous sodium sulfate concentrated

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred mixture of 3-formylbenzoic acid (450 mg, 3 mmol) in anhydrous dichloromethane (20 mL) was added triethylamine (758 mg, 7.5 mmol), 1-hydroxybenzotriazole (466 mg, 3.45 mmol), followed by 1-ethyl-3-(3-dimethylamino propyl) carbodiimide hydrochloride (629 mg, 3.45 mmol). After the addition, the mixture was stirred at room temperature for 40 mins. Then the mixture was cooled to 0° C. and cyclopropyl(piperazin-1-yl)methanone hydrochloride (629 mg, 3.3 mmol) was added in portion-wise. After the addition, the mixture was allowed to stir at room temperature overnight. The mixture was diluted with dichloromethane (50 mL), washed with saturated citric acid (100 mL×2), followed by saturated sodium bicarbonate (100 mL×2), brine (50 mL), dried over anhydrous sodium sulfate, and concentrated to give 3-(4-(cyclopropanecarbonyl)piperazine-1-carbonyl)benzaldehyde (810 mg, yield 94%) as a light yellow oil. 1H-NMR (400 MHz, CDCl3) δ (ppm): 0.79-0.85 (m, 2H), 1.00-1.04 (m, 2H), 1.73-1.76 (m, 1H), 3.47-3.77 (m, 8H), 7.62-7.66 (t, J=7.6 Hz, 1H), 7.70-7.72 (d, J=7.6 Hz, 1H), 7.95-7.98 (m, 2H), 10.1 (s, 1H); LC-MS (ESI) m/z: 287 (M+1)+. After the addition Then the mixture was cooled to 0° C. After the addition to stir at room temperature overnight washed with saturated citric acid (100 mL×2) dried over anhydrous sodium sulfate concentrated

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred mixture of 4-formylbenzoic acid (900 mg, 6 mmol) in anhydrous dichloromethane (30 mL) was added triethylamine (1.52 mg, 15 mmol), 1-hydroxybenzotriazole (891 mg, 6.6 mmol), followed by 1-ethyl-3-(3-dimethylamino propyl) carbodiimide hydrochloride (1.254 g, 6.6 mmol). After the addition, the mixture was stirred at room temperature for 40 mins. Then the mixture was cooled to 0° C. and cyclopropyl(piperazin-1-yl)methanone hydrochloride (1.259 g, 6.6 mmol) was added in portion-wise. After the addition, the mixture was allowed to stir at room temperature overnight. The mixture was diluted with dichloromethane (50 mL), washed with saturated citric acid (100 mL×2), followed by saturated sodium bicarbonate (100 mL×2), brine (50 mL), dried over anhydrous sodium sulfate, and concentrated to give 4-(4-(cyclopropanecarbonyl)piperazine-1-carbonyl)benzaldehyde (810 mg, yield 80%) as a light yellow oil. 1H-NMR (400 MHz, CDCl3) δ (ppm): 0.79-0.85 (m, 2H), 1.00-1.04 (m, 2H), 1.72-1.80 (m, 1H), 3.41-3.81 (m, 8H), 7.58-7.60 (d, J=8.0 Hz, 1H), 7.95-7.97 (d, J=8.0 Hz, 1H), 10.07 (s, 1H); LC-MS (ESI) m/z: 287 (M+1)+. After the addition Then the mixture was cooled to 0° C. After the addition to stir at room temperature overnight washed with saturated citric acid (100 mL×2) dried over anhydrous sodium sulfate concentrated

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred mixture of 4-formylbenzoic acid (900 mg, 6 mmol) in anhydrous dichloromethane (30 mL) was added triethylamine (1.52 mg, 15 mmol), 1-hydroxybenzotriazole (891 mg, 6.6 mmol), followed by 1-ethyl-3-(3-dimethylamino propyl) carbodiimide hydrochloride (1.254 g, 6.6 mmol). After the addition, the mixture was stirred at room temperature for 40 mins. Then the mixture was cooled to 0° C. and cyclopropyl(piperazin-1-yl)methanone hydrochloride (1.259 g, 6.6 mmol) was added in portion-wise. After the addition, the mixture was allowed to stir at room temperature overnight. The mixture was diluted with dichloromethane (50 mL), washed with saturated citric acid (100 mL×2), followed by saturated sodium bicarbonate (100 mL×2), brine (50 mL), dried over anhydrous sodium sulfate, and concentrated to give 4-(4-(cyclopropanecarbonyl)piperazine-1-carbonyl)benzaldehyde (810 mg, yield 80%) as a light yellow oil. 1H-NMR (400 MHz, CDCl3) δ (ppm): 0.79-0.85 (m, 2H), 1.00-1.04 (m, 2H), 1.72-1.80 (m, 1H), 3.41-3.81 (m, 8H), 7.58-7.60 (d, J=8.0 Hz, 1H), 7.95-7.97 (d, J=8.0 Hz, 1H), 10.07 (s, 1H); LC-MS (ESI) m/z: 287 (M+1)+. After the addition Then the mixture was cooled to 0° C. After the addition to stir at room temperature overnight washed with saturated citric acid (100 mL×2) dried over anhydrous sodium sulfate concentrated

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred mixture of compound tert-butyl 4-(cyclopropanecarbonyl)piperazine-1-carboxylate (3.7 g, 14.5 mmol) in methanol (15 mL) was added hydrochloride/methanol (15 mL, 3M)) at 0° C. After the addition, the mixture was allowed to stir at room temperature overnight. The mixture was concentrated to give cyclopropyl(piperazin-1-yl)methanone hydrochloride (2.74 g, yield 100%) as an off-white solid. 1H-NMR (400 MHz, DMSO-d6) δ (ppm): 0.71-0.76 (m, 4H), 1.96-2.03 (m, 1H), 3.04-3.16 (m, 4H), 3.69-4.08 (m, 4H), 9.58 (s, 2H); LC-MS (ESI) m/z: 155(M+1)+. After the addition The mixture was concentrated

Conditions: temp:40.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Acetic acid (700 ml) was treated with piperazine (50.00 g, 0.581 mol) portionwise over 15 minutes with stirring under nitrogen The reaction mixture was warmed to 40° C. and maintained at this temperature until a complete solution was obtained. Cyclopropanecarbonyl chloride 59.2 ml, 0.638 mol) was added over 15 minutes. The reaction mixture was stirred at room temperature overnight. The reaction mixture was filtered and the filtrate distilled under reduced pressure until ˜430 ml of distillates had been collected. Toluene (550 ml) was charged to the reaction mixture and reduced pressure distillation continued until a further 400 ml of distillates were collected. A further charge of toluene (550 ml) was added and reduced pressure distillation continued until 350 ml of distillates were collected. The resulting slurry was diluted with toluene (200 ml) and stirred overnight. Further toluene (500 ml) was added in order to mobilise the slurry. The slurry was filtered, washed with toluene (100 ml) and dried in vacuo at 40° C. to give the title compound as an off white solid (86.78 g). maintained at this temperature until a complete solution was obtained The reaction mixture was stirred at room temperature overnight The reaction mixture was filtered the filtrate distilled under reduced pressure until ˜430 ml of distillates had been collected Toluene (550 ml) was charged to the reaction mixture and reduced pressure distillation were collected A further charge of toluene (550 ml) was added reduced pressure distillation were collected The resulting slurry was diluted with toluene (200 ml) stirred overnight Further toluene (500 ml) was added in order The slurry was filtered washed with toluene (100 ml) dried in vacuo at 40° C.

Conditions: temp:40.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Acetic acid (700 ml) was treated with piperazine (50.00 g, 0.581 mol) portionwise over 15 minutes with stirring under nitrogen The reaction mixture was warmed to 40° C. and maintained at this temperature until a complete solution was obtained. Cyclopropanecarbonyl chloride 59.2 ml, 0.638 mol) was added over 15 minutes. The reaction mixture was stirred at room temperature overnight. The reaction mixture was filtered and the filtrate distilled under reduced pressure until 430 ml of distillates had been collected. Toluene (550 ml) was charged to the reaction mixture and reduced pressure distillation continued until a further 400 ml of distillates were collected. A further charge of toluene (550 ml) was added and reduced pressure distillation continued until 350 ml of distillates were collected. The resulting slurry was diluted with toluene (200 ml) and stirred overnight. Further toluene (500 ml) was added in order to mobilise the slurry. The slurry was filtered, washed with toluene (100 ml) and dried in vacuo at 40° C. to give the title compound as an off white solid (86.78 g). maintained at this temperature until a complete solution was obtained The reaction mixture was stirred at room temperature overnight The reaction mixture was filtered the filtrate distilled under reduced pressure until 430 ml of distillates had been collected Toluene (550 ml) was charged to the reaction mixture and reduced pressure distillation were collected A further charge of toluene (550 ml) was added reduced pressure distillation were collected The resulting slurry was diluted with toluene (200 ml) stirred overnight Further toluene (500 ml) was added in order The slurry was filtered washed with toluene (100 ml) dried in vacuo at 40° C.

Conditions: temp:40.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Acetic acid (700 ml) was treated with piperazine (50.00 g, 0.581 mol) portionwise over 15 minutes with stirring under nitrogen The reaction mixture was warmed to 40° C. and maintained at this temperature until a complete solution was obtained. Cyclopropanecarbonyl chloride 59.2 ml, 0.638 mol) was added over 15 minutes. The reaction mixture was stirred at room temperature overnight. The reaction mixture was filtered and the filtrate distilled under reduced pressure until 430 ml of distillates had been collected. Toluene (550 ml) was charged to the reaction mixture and reduced pressure distillation continued until a further 400 ml of distillates were collected. A further charge of toluene (550 ml) was added and reduced pressure distillation continued until 350 ml of distillates were collected. The resulting slurry was diluted with toluene (200 ml) and stirred overnight. Further toluene (500 ml) was added in order to mobilise the slurry. The slurry was filtered, washed with toluene (100 ml) and dried in vacuo at 40° C. to give the title compound as an off white solid (86.78 g). maintained at this temperature until a complete solution was obtained The reaction mixture was stirred at room temperature overnight The reaction mixture was filtered the filtrate distilled under reduced pressure until 430 ml of distillates had been collected Toluene (550 ml) was charged to the reaction mixture and reduced pressure distillation were collected A further charge of toluene (550 ml) was added reduced pressure distillation were collected The resulting slurry was diluted with toluene (200 ml) stirred overnight Further toluene (500 ml) was added in order The slurry was filtered washed with toluene (100 ml) dried in vacuo at 40° C.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred mixture of 3-formylbenzoic acid (450 mg, 3 mmol) in anhydrous dichloromethane (20 mL) was added triethylamine (758 mg, 7.5 mmol), 1-hydroxybenzotriazole (466 mg, 3.45 mmol), followed by 1-ethyl-3-(3-dimethylamino propyl) carbodiimide hydrochloride (629 mg, 3.45 mmol). After the addition, the mixture was stirred at room temperature for 40 mins. Then the mixture was cooled to 0° C. and cyclopropyl(piperazin-1-yl)methanone hydrochloride (629 mg, 3.3 mmol) was added in portion-wise. After the addition, the mixture was allowed to stir at room temperature overnight. The mixture was diluted with dichloromethane (50 mL), washed with saturated citric acid (100 mL×2), followed by saturated sodium bicarbonate (100 mL×2), brine (50 mL), dried over anhydrous sodium sulfate, and concentrated to give 3-(4-(cyclopropanecarbonyl)piperazine-1-carbonyl)benzaldehyde (810 mg, yield 94%) as a light yellow oil. 1H-NMR (400 MHz, CDCl3) δ (ppm): 0.79-0.85 (m, 2H), 1.00-1.04 (m, 2H), 1.73-1.76 (m, 1H), 3.47-3.77 (m, 8H), 7.62-7.66 (t, J=7.6 Hz, 1H), 7.70-7.72 (d, J=7.6 Hz, 1H), 7.95-7.98 (m, 2H), 10.1 (s, 1H); LC-MS (ESI) m/z: 287 (M+1)+. After the addition Then the mixture was cooled to 0° C. After the addition to stir at room temperature overnight washed with saturated citric acid (100 mL×2) dried over anhydrous sodium sulfate concentrated

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred mixture of 4-formylbenzoic acid (900 mg, 6 mmol) in anhydrous dichloromethane (30 mL) was added triethylamine (1.52 mg, 15 mmol), 1-hydroxybenzotriazole (891 mg, 6.6 mmol), followed by 1-ethyl-3-(3-dimethylamino propyl) carbodiimide hydrochloride (1.254 g, 6.6 mmol). After the addition, the mixture was stirred at room temperature for 40 mins. Then the mixture was cooled to 0° C. and cyclopropyl(piperazin-1-yl)methanone hydrochloride (1.259 g, 6.6 mmol) was added in portion-wise. After the addition, the mixture was allowed to stir at room temperature overnight. The mixture was diluted with dichloromethane (50 mL), washed with saturated citric acid (100 mL×2), followed by saturated sodium bicarbonate (100 mL×2), brine (50 mL), dried over anhydrous sodium sulfate, and concentrated to give 4-(4-(cyclopropanecarbonyl)piperazine-1-carbonyl)benzaldehyde (810 mg, yield 80%) as a light yellow oil. 1H-NMR (400 MHz, CDCl3) δ (ppm): 0.79-0.85 (m, 2H), 1.00-1.04 (m, 2H), 1.72-1.80 (m, 1H), 3.41-3.81 (m, 8H), 7.58-7.60 (d, J=8.0 Hz, 1H), 7.95-7.97 (d, J=8.0 Hz, 1H), 10.07 (s, 1H); LC-MS (ESI) m/z: 287 (M+1)+. After the addition Then the mixture was cooled to 0° C. After the addition to stir at room temperature overnight washed with saturated citric acid (100 mL×2) dried over anhydrous sodium sulfate concentrated

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred mixture of compound tert-butyl 4-(cyclopropanecarbonyl)piperazine-1-carboxylate (3.7 g, 14.5 mmol) in methanol (15 mL) was added hydrochloride/methanol (15 mL, 3M)) at 0° C. After the addition, the mixture was allowed to stir at room temperature overnight. The mixture was concentrated to give cyclopropyl(piperazin-1-yl)methanone hydrochloride (2.74 g, yield 100%) as an off-white solid. 1H-NMR (400 MHz, DMSO-d6) δ (ppm): 0.71-0.76 (m, 4H), 1.96-2.03 (m, 1H), 3.04-3.16 (m, 4H), 3.69-4.08 (m, 4H), 9.58 (s, 2H); LC-MS (ESI) m/z: 155 (M+1)+. After the addition The mixture was concentrated

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred mixture of 3-formylbenzoic acid (450 mg, 3 mmol) in anhydrous dichloromethane (20 mL) was added triethylamine (758 mg, 7.5 mmol), 1-hydroxybenzotriazole (466 mg, 3.45 mmol), followed by 1-ethyl-3-(3-dimethylamino propyl)carbodiimide hydrochloride (629 mg, 3.45 mmol). After the addition, the mixture was stirred at room temperature for 40 mins. Then the mixture was cooled to 0° C. and cyclopropyl(piperazin-1-yl)methanone hydrochloride (629 mg, 3.3 mmol) was added in portion-wise. After the addition, the mixture was allowed to stir at room temperature overnight. The mixture was diluted with dichloromethane (50 mL), washed with saturated citric acid (100 mL×2), followed by saturated sodium bicarbonate (100 mL×2), brine (50 mL), dried over anhydrous sodium sulfate, and concentrated to give 3-(4-(cyclopropanecarbonyl)piperazine-1-carbonyl)benzaldehyde (810 mg, yield 94%) as a light yellow oil. 1H-NMR (400 MHz, CDCl3) δ (ppm): 0.79-0.85 (m, 2H), 1.00-1.04 (m, 2H), 1.73-1.76 (m, 1H), 3.47-3.77 (m, 8H), 7.62-7.66 (t, J=7.6 Hz, 1H), 7.70-7.72 (d, J=7.6 Hz, 1H), 7.95-7.98 (m, 2H), 10.1 (s, 1H); LC-MS (ESI) m/z: 287 (M+1)+. After the addition Then the mixture was cooled to 0° C. After the addition to stir at room temperature overnight washed with saturated citric acid (100 mL×2) dried over anhydrous sodium sulfate concentrated